<div class="buttonGroupDirective" >
    <button type="button" class="btn active" ng-click="handle()">第一学期</button>
    <button type="button" class="btn">第二学期</button>
    <button type="button" class="btn">第三学期</button>
    <button type="button" class="btn">第四学期</button>
    <button type="button" class="btn">第五学期</button>
</div>